Pattern device for circular knitting machines



Mard a 10, 1970 P zAHRAoKA PATTERN DEVICE FOR CIRCULAR KNITTING MACHINES 2 Sheets-Sheet 1 Filed June 26, 1967 March 10,1970 'F"- ZA/HRDKA' 3,499,360

, PATTERN mzvxcr: FOR CIRCULAR mums uacamns Filed June 26, 1967 2 Sheets-Sheet z United States Fatent Ofilice 3,499,300 Patented Mar. 10, 1970 3,499,300 PATTERN DEVICE FOR CIRCULAR KNITTING MACHINES Pavel Zahradka, Trebic, Czechoslovakia, assiguor to Elitex, Zavody Textilniho Strojirenstvi Generalni Reditelstvi, Liberec, Czechoslovakia Filed June 26, 1967, Ser. No. 649,434

Claims priority, application Czechoslovakia, July 1, 1966,

4,420/ 66 Int. Cl. D46b 15/16 US. Cl. 6614 3 Claims ABSTRACT OF THE DISCLOSURE A circular knitting machine wherein jacks are shiftable in the direction of needle movement and respectively terminate in butt ends which during rotation with the needle cylinder move past and in close proximity to a needle-selecting station where an electromagnetic means is located. This electromagnetic means will act magnetically on selected jacks to displace them in their grooves in the direction of needle movement, and a cam means coacts with the shifted jacks to tilt them in their grooves so that they will coact with further cam means in a manner differently from non-selected jacks.

BACKGROUND OF THE INVENTION The invention relates to circular knitting machines having electromagnetic pattern devices.

In particular, the invention relates to that type of circular knitting machine where there are situated beneath the needles, in longitudinal axial grooves of the needle cylinder, shiftable jacks capable of being selected by means of a stationary electromagnetic means with respect to which the needle cylinder and structure carried thereby rotates, so that certain needles can be selected according to a predetermined pattern.

According to certain known constructions of devices of this type, movable electromagnetic armatures are used, which take the form of impact hammers that act to displace jack-shifting elements situated in the immediate vicinity of the jacks so as to act to displace jacks which are selected according to a predetermined pattern. As a result of the. relatively large swinging masses of the electromagnetic armatures, such devices are incapable of providing a satisfactory needle selection with relatively fine needle distribution in the needle cylinder and at high speeds of rotation of the needle cylinder.

Furthermore, a construction of the latter type requires a large amount of space and therefore cannot be used with a circular knitting machine having a relatively large number of knitting systems for providing knitted hose. The structure has an assembly of springs which are bent at right angles, and radially shiftable pattern plates, so

that these latter features together with the requirement of tensioning of the individual springs give rise to faulty operation and the requirement of a large amount of maintenance and service. by the operating personnel.

With other known structures of this general type, the needle jacks come under the influence of a stationary electromagnet with respect to which the needle cylinder rotates, this electromagnet selecting the jacks by radially pulling them out of their grooves into the region of cams having oppositely inclined camming surfaces and forming part of a stationary cam cylinder, so that these oppositely inclined cam surfaces join each other to form a V-shaped cam. A disadvantage of this type of construction resides in the fact that at high speed rotation of the needle cylinder there is no satisfactory and sufficient radial displacement of the selected jacks as is essential for satisfactory coaction between the jacks and the camming edges.

SUMMARY OF THE INVENTION It is accordingly a primary object of the present invention to eliminate the above drawbacks.

In particular it is an object of the present invention to provide for a circular knitting machine a pattern device capable of selecting jacks and thus moving the needles which are controlled thereby in a manner which is far simpler than has heretofore been possible.

Furthermore, it is an object of the present invention to provide a construction which is capable of providing an accurate and faultless jack selection even with relatively fine distribution of the needle jacks in the needle cylinder and at high speeds of rotation of the latter.

In accordance with the present invention, the jacks which are selected are displaced in the direction of needle movement longitudinally of the cylinder grooves in which the jacks are located by the. action of an electromagnetic means which thus displaces the selected jacks axially in the direction of needle movement, the jacks controlling the movement, for example, of needle plates Which carry the needles and are controlled by the jacks.

BRIEF DESCRIPTION OF DRAWINGS The invention is illustrated by way of example in the accompany drawings which form part of this application and in which:

FIG. 1 is a fragmentary axial section of a needle cylinder, the plane of the section of FIG. 1 being taken in a groove of the needle cylinder, FIG. 1 fragmentarily showing the electromagnetic means which brings about the movement of a selected jack;

FIG. 2 shows the structure of FIG. 1 after it has been actuated to displace a selected jack;

FIG. 3 is a fragmentary schematic developed view of part of the needle cylinder showing also the cam means which coacts therewith; and

FIG. 4 is a fragmentary schematic top plan view taken in the direction of the arrow IV of FIG. 3, showing the construction along the upper edge of an intermediate cam cylinder which coacts with the selected jacks.

DESCRIPTION OF A PREFERRED EMBODIMENT Referring now to the drawings, the embodiment of the invention which is illustrated therein includes the fragmentarily illustrated needle cylinder 2 formed with the axial grooves 1 in which the axially shiftable jacks 3 are respectively located. The needle cylinder 2 is rotated in a well known manner, and the jacks 3 which are selected by the pattern device' are electromagnetically pulled downwardly, as viewed in FIG. 1, by an electromagnet 15 which is schematically illustrated in FIGS. 1 and 2. This electromagnet which is situated at the selecting station is stationary so that the needle cylinder 2 and the structure carried thereby rotates with respect to the stationary electromagnetic selecting means.

FIG. 1 shows a jack 3 which is about to be selected but which is shown in FIG. 1 in its normal or initial rest position in which it enters the selecting station before it is pulled downwardly. In FIG. 2, which is the same sectional view as FIG. 1, the selected jack 3 is shown after it has been shifted downwardly by the magnetic force of the electromagnet 15..

A cam means is provided to control the movements of the jacks, according to whether they are selected or not by the electromagnet 15, and this cam means includes the upper cam ring 9, the intermediate cam ring 10, and the lower cam ring 11, all of which are stationary and surround the rotary needle cylinder 2. Thus, as may be seen from FIG. 3, which is a fragmentary schematic developed view of the structure, the needle cylinder 2 moves in the direction of the arrow S, to the left as viewed in FIG. 3, so that in this way the jacks also move to the left, as viewed in FIG. 3, with respect to the stationary carn rings 9-11.

The structure of the invention which is illustrated in the drawings, may be used, for example, in the manufacture of fine seamless ladies stockings, and only those components of the apparatus are illustrated which are directly related to the invention.

Within the axial grooves 1 of the needle cylinder 2 are situated the jacks 3 which have, respectively, upper cam follower projections 4, lower cam follower projections 5, respectively and the jacks 3 respectively terminate at their bottom ends in butts 6 which have lower operating surfaces 7. Situated above the upwardly tapered upper portions 3a of the jacks 3 are the needle plates as sliders 8 in which unillustrated double-tongued needles are hung. The jacks 3 are held in the needle cylinder 2 by means of the stationary cam rings 9-11 between which the cam follower projections 4 and are situated for movement in the direction of the arrow S of FIG. 3. At the selecting station Where certain jacks are selected for shifting movement by the electromagnetic action of the electromagnet 15, the intermediate cam ring 10 is provided along its upper edge with an upwardly directed cutout 12 (FIGS. 3 and 4), and at this cutout the cam ring 10 has an inclined control edge or auxiliary cam 14 while the lower cam ring 11 has at its upper edge, directly beneath the cutout 12, the cutout 13. The configuration of the cutout 12 is such that as the cam followers 4 pass therethrough they are suddenly freed at their lower faces so that the jacks, if selected, are free to be displaced downwardly in a direction extending parallel to the axis of the needle cylinder.

By way of the electromagnet 15, a selected jack 3 will be pulled downwardly to the position of.FIG. 2, and thus a selected jack will have its carn follower 4 acted upon by the inclined edge 14 which thus pushes the cam follower 4 of the selected jack radially toward the axis of the needle cylinder so that the upper tapered ends 3a of the selected jacks are radially displaced further into the grooves 1. On the other hand, those jacks 3 which are not selected and which thus remain at their initial elevations clear the edge or auxiliary cam 14 and are only displaced downwardly when their cam followers 4 engages the downwardly inclined edge 16 of the upper cam ring 9. As a result of the action of the camming portion 16 of the upper ring 9, the lower cam followers 5 become situated beneath the cam 17. At the same time, the lower cam followers 5 of the selected needle which have been tilted in the cylinder grooves 1, engage the cam 17 to be raised upwardly thereby to an upper operating position, because the inward displacement of the upper cam followers 4 situated these upper cam followers at locations where they are situated beyond the edge 16 and thus do not engage the latter so that the selected needles are not pushed down by the camming edge 16.

For the purpose of providing a perfectly satisfactory operation and maximum electromagnetic action of the electromagnet at its working end surface or pole face 18, the needle cylinder has its grooves 1 provided with bottom open ends through and beyond which the butt ends 6 of the jacks 3 respectively project. Below the bottom open ends of the grooves 1, the cylinder 2 carries a nonmagnetic ring 19 formed at its inner surface with .a series of axial grooves which are respectively aligned with and form extensions of the grooves 1, so that the butt ends 6 of the jacks 3 respectively received in these grooves of the non-magnetic ring 19 whose lower face is situated at the elevation of the face 18 of the electromagnet 15. Thus, as a result of rotation of the needle cylinder 2 in the direction of the arrow S of FIG. 4, the

jacks are controlled by the section of the cam rings 9-11 shown in FIG. 3.

The above described structure operates as follows:

When a given needle plate 8 is to be selected so that the unillustrated needle carried thereby will come into operation, through an unillustrated and known control means the electromagnet is excited, this electromagnet being stationary and located at a lower portion of the needle cylinder 2 at the selecting station. As a result of the action of the surface 18 of the electromagnet 15 on the surface 7 at the bottom end of the jack butt 6 of a selected jack, an electromagnetic force is developed which axially displaces the selected jack 3 by the distance A indicated in FIG. 1. As a result the upper cam follower 4 of the selected jack enters into the cutout 12 of the intermediate cam ring 10, and the lower cam follower 5 of the selected jack simultaneously enters into the cutout 13 of the lower cam ring 11. During the continued rotation of the needle cylinder 2 in the direction of the arrow S, the upper cam follower of the selected jack engages the inclined camming edge 14 of the intermediate cam ring 10, so that the upper tapered portion 3a of the selected jack is pressed further into the groove 1 and the selected needle jack thus tilts within the cylinder groove. During the further rotation of the needle cylinder, the lower cam follower 5 of the selected jack 3 reliably reaches the inclined edge of the cam 17 shown in FIG. 3, so that in this way the selected jack 3 together with the needle plate 8 which cooperates therewith are brought into their upper operating position for the purpose of providing the preselected pattern.

Every jack 3 which is thus selected and raised in this manner again reaches its initial position as a result of the action of the lowering cam edge 20 of the intermediate cam ring 10 on the lower cam follower 5.

Each of those jacks 3 which are not selected and which are thus not acted upon by the electromagnetic 15 do not come into engagement with the camming edge 14 at their upper cam followers 4 and thus remain in the grooves 1 of the needle cylinder without being displaced therein. During the further rotation of the needle cylinder the nonselected jacks are acted upon by the lowering cam edge 16 of the upper ring 9 so that they are lowered to such an elevation that their lower cam followers 5 become situated beneath the cam 17 and thus these non-selected jacks do not have any influence on the needle plates 8 which coact therewith, and therefore the needles carried by the latter needle plates do not enter into the operations.

In order to intensify the electromagnetic action of the electromagnet 15 on the operating surfaces 7 of the lower jack butts 6, these surfaces 7 are situated outwardly beyond the lower open ends of the grooves 1 of the needle cylinder 2, so that substantial portions of the butts 6 are situated in the grooves of the non-magnetic ring 19.

I claim:

1. In a circular knitting machine, a rotary needle cylinder formed with a plurality of longitudinal grooves, needle means situated for movement in said grooves, a plurality of needle jacks respectively situated in said grooves and respectively terminating in butt ends, said jacks being shiftable in said grooves in the direction of needle movement, stationary eleceromagnetic means coacting with the said butt ends of said jacks for longitudinally shifting selected jacks in said grooves in the direction of needle movement, said grooves of said cylinder respectively terminating in open ends through and beyond which said butt ends of said jacks project, and a nonmagnetic ring carried by the needle cylinder at said open ends of said grooves thereof, and said ring being formed with axial grooves respectively forming extensions of said grooves of said cylinder for receiving the butt ends of said jacks which project beyond said grooves of said cylinder.

2. In a knitting machine having a needle cylinder rotatable about the axis thereof and formed with a plurality of circumferentially distributed axially elongated grooves, an elongated jack and an elongated needle means longitudinally and axially shiftable in each groove, said jack having an end portion remote from said needle means, a jack selecting station sequentially alignable with said grooves during rotation of said cylinder, each jack assuming a normal axial and radial position when said jack approaches said station, and cam means for axially shifting selected jacks into a first position, and for axially shifting nonselected jacks into a second position when said jacks move away from said station, the improvement in the selecting station which comprises:

(a) a stationary electromagnet having a pole face axially spaced from said end portion of a jack, when said jack is in said normal axial position in the groove aligned with said selecting station, said face being directed toward said end portion for attracting and axially moving said jack when said electromagnet is excited; and

(b) auxiliary cam means clearing said jack when in said normal axial position and engaging said jack, when the jack is attracted and moved by said electromagnet, for shifting the engaged jack radially inward of the associated groove from said normal radial position in response to the rotation of said cylinder, and for thereby selecting the attracted and axially moved jack, the jacks passing said selecting station in the normal radial position constituting said non-selected jacks. 3. In a knitting machine as set forth in claim 2, said auxiliary cam means angularly shifting said engaged jack inward of said associated groove.

References Cited UNITED STATES PATENTS WM. CARTER REYNOLDS, Primary Examiner US. Cl. X.R. 

